unsatfit is a Python library for optimizing parameters of functions of soil hydraulic properties; water retention function and unsaturated hydraulic conductivity function. The equations are explained in Seki et al. (2022) and shown to be useful for practical applications in Seki et al. (2023).

See the full document at https://arxiv.org/abs/2302.00472

See the quick reference at https://sekika.github.io/unsatfit/

This is an example output of this program; water retention curve (top) and hydraulic conductivity curve (bottom) of Gilat loam fitted with KBC (KO₁BC₂-CH) model.

SWRC Fit is a web interface which uses unsatfit and determines parameters for water retention function.

• SWRC Fit

• Seki, K., Toride, N., & Th. van Genuchten, M. (2022) Closed-form hydraulic conductivity equations for multimodal unsaturated soil hydraulic properties. Vadose Zone J. 21; e20168. https://doi.org/10.1002/vzj2.20168
• Seki, K., Toride, N., & Th. van Genuchten, M. (2023) Evaluation of a general model for multimodal unsaturated soil hydraulic properties. J. Hydrol. Hydromech. 71(1): 22-34. https://doi.org/10.2478/johh-2022-0039